In recent years, the number of people living alone has been increasing, and people tend to have less relationships with their neighbors. A person who lives alone and does not have relationship with his/her neighbors cannot notify people around him/her if an abnormality (for example, an accident or illness that may lead to death) happens concerning the person. To prevent such an event, various safety confirmation systems have been devised. Such a safety confirmation system is useful for, for example, relatives of a person living alone to confirm whether the person living alone is safe. It is also useful for an owner of a condominium to know early of an abnormality to the person living alone in the condominium and prevent the room and condominium from being spoiled due to decomposition of a body.
The above-mentioned systems include a system using an electronic kettle. Specifically, when a person living alone uses an electronic kettle, the kettle sends information notifying that the kettle is used to a surveillant terminal. The surveillant terminal displays the sent information on a display, and the surveillant determines whether the person living alone is safe because of the use of the kettle.
Methods in which a sensor is arranged in a living space are also used. Specifically, each time a sensor arranged in a living space detects that an object moves in the detection area of the sensor, it sends the detection information to a surveillant terminal. The surveillant terminal displays the sent detection information on a display, and the surveillant determines whether the person living alone is safe on the basis of the detection information. Japanese Laid-open Patent Publication No. 2002-24966 discloses a technology that enables the above method using a hidden sensor.
Japanese Laid-open Patent Publication No. 07-148122 discloses an emergency notifying system using a pedometer. Specifically, an old person living alone carries a pedometer, and the pedometer periodically sends information on the number of steps the old person makes to a nursing care center. In the nursing care center, a central unit determines the health condition of the old person on the basis of the level of the sent step-number information (for example, if the number of steps in a day is 200 or less, it is determined that the old person has become ill). When it is determined that an abnormality has happened, the manager confirms whether the old person is safe by, for example, making a call to the old person.
Japanese Laid-open Patent Publication No. 2005-182411 discloses, as a method of maintaining the safety of people living alone, a method in which a sensor to detect a fingerprint is arranged on a button on an entrance intercom. When a resident presses the button, the voice of another person is output from the intercom's speaker so that people think that there is somebody living with the resident.
However, the above-described technology only allows the surveillant to determine whether an abnormality has happened concerning the monitoring subject and has a problem in that reliable information cannot be provided.
Specifically, for the technology in which the use of the electric kettle is displayed on the display of the surveillant terminal, the monitoring subject uses the electric kettle arbitrarily, so the use may be terminated in the summer time or, even if the kettle is usually used, the kettle may still sometimes not be used. As described above, even through the monitoring subject is normal, the surveillant may make an erroneous determination because information representing the use of the kettle is received at longer intervals. Therefore, the surveillant only determines whether an abnormality has happened concerning the monitoring subject, and reliable information cannot be provided.
In the technology in which information that is sensed by the sensor, which is arranged in the living space, is displayed on the display of the surveillant terminal (the technology disclosed in Japanese Laid-open Patent Publication No. 2002-24966), even if, for example, the monitoring subject has already died, the sensor may keep sensing a small animal moving or a curtain moving by a window. Because, as in the above case, detection information may continue to be sent and the surveillant may make an erroneous determination even though an abnormality has happened concerning the monitoring subject, the surveillant only determines whether an abnormality has happened concerning the monitoring subject, and reliable information cannot be provided. Furthermore, in achieving such a system, there is a problem in that, in many cases, it is necessary to make a contract with a security company and modify the residence, i.e., the system is not applicable to the current living space.
In the technology disclosed in Japanese Laid-open Patent Publication No. 07-148122, it is necessary for a monitoring subject to carry a pedometer, but he/she may forget to carry the pedometer. As described above, even though the monitoring subject is normal, step-number information may not be sent and the surveillant may make an erroneous determination. Thus, the surveillant only determines whether an abnormality has happened concerning the monitoring subject, and reliable information cannot be provided.